The neutral pH is 7. Less than 7 indicates an acid and more than 7 indicates a base (up to 14).
<span>
NaCl - it's a salt (we can't measure the pH)
H2O - it can be an acid but also a base (the pH it is almost neutral,meaning close to 7 )
HF - it is a strong acid
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KOH
- it is a strong base (pH=14)
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He needs to use HF (Hydrogen fluoride) to decrease the pH.
Answer:
0.6
Explanation:
The volume of a sphere = 
Therefore 
r of the disc = 
Using conservation of angular momentum;
The
of the sphere = 
of the disc = 

= 0.6
<u>Answer:</u>
Velocity of the dog relative to the road = 26.04 m/s 3.15⁰ north of east.
<u>Explanation:</u>
Let the east point towards positive X-axis and north point towards positive Y-axis.
Speed of truck = 25 m/s north = 25 j m/s
Speed of dog = 1.75 m/s at an angle of 35.0° east of north = (1.75 cos 35 i + 1.75 sin 35 j)m/s
= (1.43 i + 1.00 j) m/s
Velocity of the dog relative to the road = 25 j + 1.43 i + 1.00 j = 1.43 i + 26.00 j
Magnitude of velocity = 26.04 m/s
Angle from positive horizontal axis = 86.85⁰
So Velocity of the dog relative to the road = 26.04 m/s 86.85⁰ east of north = 26.04 m/s 3.15⁰ north of east.
Question 1:
Answer:
The moment of inertia of Alex's rolling hoop is 0.197 
Explanation:
<u>Given</u>:
Mass of the hoop = 0.350 g
Radius of the hoop = 75.0 cm
<u>To Find:</u>
The moment of inertia of Alex's rolling hoop = ?
<u>Solution</u><u>:</u>
The moment of inertia = 
where
m is the mass
r is the radius
Converting cm to m, we get
75.0 cm = 0.75 m
Now substituting the values,
=> moment of inertia = 
=> moment of inertia = 
=> moment of inertia = 
Question 2:
Answer:
The combined angular momentum of the masses is 1.76 
If she pulls her arms in to 0.12 m, her new linear speed is 
Explanation:
Given:
Mass = 2.0 kg
Radius = 0.8 m
Velocity = 1.2 m/s
a.The combined angular momentum of the masses:

Substituting the values,

L= 1.76 
b. If she pulls her arms in to 0.12 m, what is her new linear speed




Impulse is equal to change in momentum. So if impulse is 2000 then to solve for new velocity we just set it equal to equation for momentum.
First find original momentum by p=mv
p=1000*20=20000
So then taking that value minus the impulse since it was in opposite direction of original momentum it will slow it down some. To find new velocity we just take
20000-2000=18000=mv
v=18000/1000 =18m/s
Hope this helps!! Any questions please ask!!
Thank you!